Wikia

Cellular biology is the branch of biology that studies cells.

In one of the letters left by Raymond Marr, which were contained in the colonist's files possessed by Data, Marr stated to his mother, that he "took my last exam today. I think I did alright on everything except cellular biology. I know you think it's important, Mom, but I don't see how I'm ever gonna use that stuff." (TNG: "Silicon Avatar")